Behroze Vachha, Maryellen R. M. Sun Bettina Siewert Ronald L. Eisenberg
Cystic liver lesions, or fluid-containing lesions of the liver, are commonly encountered findings on radiologic examinations that may represent a broad spectrum of entities ranging from benign developmental cysts to malignant neoplasms (Table 1). The wide range of pathologic processes that may result in cystic liver lesions can present a difficult diagnostic conundrum. The radiologist must carefully assess such imaging features as location, size, and unifocal or multifocal nature of the cyst or cysts as well as evaluate cyst complexity and as-sociated findings. In addition, because radiologic features of various cystic liver lesions overlap, it is necessary to integrate imaging with clinical and laboratory findings to allow more definitive diagnosis. An important first step in narrowing the differential diagnosis is to determine the presence or absence of complex features in cystic liver lesions. To this end, fluid-containing liver lesions can be grouped broadly into simple or complex cysts.